Known technologies in conventional car navigation devices include, for instance, route guidance technologies in which an on-board camera captures images ahead of a vehicle during cruising, and guidance information, in the form of CG (Computer Graphics), is displayed with being overlaid on video obtained through the above image capture (for instance, Patent Document 1).
As a similar technology, Patent Document 2 discloses a car navigation device in which navigation information elements are displayed so as to be readily grasped intuitively. In this car navigation device, an imaging camera attached to the nose or the like of a vehicle captures the background in the travel direction, in such a manner that a map image and a live-action video with respect to background display of navigation information elements can be selected by a selector, and the navigation information elements are displayed on a display device with being overlaid on the background image by way of an image composition unit. Patent Document 2 indicates that besides live-action video, there can also be displayed simultaneously a map having a different display mode or scale, and discloses a technique for displaying conventional maps side by side.
Patent Document 1: Japanese Patent No. 2915508
Patent Document 2: Japanese Patent Application Publication No. 11-108684 (JP-A-11-108684)
Meantime, since the road to be guided runs between buildings and the like along the road, it is desirable that guidance information to be superimposed on the video is properly overlaid on the buildings on the video. In the above conventional technologies, however, guidance information is simply superimposed on a video, and hence the guidance information is displayed closer in the foreground than (or before) all the elements on the video (buildings, signboards and the like). As a result, there is a possibility for a user to grasp an intersection to be turned erroneously.
The present invention is made to solve the aforementioned problem, and it is an object of the present invention to provide a navigation device capable of displaying suitably guidance information on a real video.